1. Field of the Disclosure
Aspects of the present disclosure relate to an apparatus for stacking veneer sheets, said apparatus comprising conveyor means for delivering veneer sheets to a stacking point and means for placing veneer sheets on a stack to be formed.
2. Description of Related Art
When it is desirable to conduct the stacking of veneer sheets automatically, the most common practice today is the use of a stacker designed with a suction belt. Applications also exist, which employ a mechanical stacker, e.g. in a jointer. It comprises belts with a veneer proceeding therebetween, and the stacking is performed by moving the lower belt aside.
The suction belt stacker is a working solution as such, but it takes a considerable amount of electric power as suction must be generated by electric motor-driven fans. It may further cause an environmental hazard by swirling air. An attempt to control this environmental problem has been made by using a filtering station. The fans may additionally cause noise problems. The suction belt stacker may have a limited applicability in terms of stacking thin veneer, e.g. as a result of suction adjustment and the fact that releasing a thin veneer from suction may break the veneer. In addition, the stacking accuracy is poor in a suction belt stacker as the veneer moves forward during the course of stacking and e.g. the inconstant weight of veneer has an impact on where the veneer finally comes to a stop. The stacking accuracy is also influenced by the distance between stack and stacker. The stack must have its top surface relatively far away from the suction belt to prevent the veneer sheet from rising back to the belt as a result of suction. Although regulated by a photocell, the distance nevertheless varies, e.g. the distance between various ends of the stack may be different.
There is no knowledge of a useful mechanical stacker. The drawbacks in today's mechanical stackers, wherein veneer sheets are carried between belts, include slowness, a difficulty in managing to retain the veneer in alignment between the belts, and the entrapment of air underneath the veneer as it settles on a veneer stack.